stus = [
    [2014111,97,92,81,60],
    [2014113,65,92,81,60],
    [2014112,87,99,81,60],
    [2014114,34,92,81,60],
    [2014116,34,92,81,60],
    [2014115,23,92,81,60],
]


for stu in stus:
    print(stu)
    avg = sum(stu[1:])/4
    stu.append(avg)

stus.sort(key=lambda stu:stu[0])

print("学号","平均成绩")
for stu in stus:
    print(stu[0],stu[5])
    
